xref: /netbsd-src/sys/kern/kern_reboot.c (revision 53b02e147d4ed531c0d2a5ca9b3e8026ba3e99b5)
1 /*	$NetBSD: kern_reboot.c,v 1.4 2020/02/23 22:56:41 ad Exp $	*/
2 
3 /*
4  * Copyright (c) 1982, 1986, 1989, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  *
31  *	@(#)kern_xxx.c	8.3 (Berkeley) 2/14/95
32  *	from: NetBSD: kern_xxx.c,v 1.74 2017/10/28 00:37:11 pgoyette Exp
33  */
34 
35 #include <sys/cdefs.h>
36 __KERNEL_RCSID(0, "$NetBSD: kern_reboot.c,v 1.4 2020/02/23 22:56:41 ad Exp $");
37 
38 #include <sys/atomic.h>
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/proc.h>
42 #include <sys/reboot.h>
43 #include <sys/syscall.h>
44 #include <sys/syscallargs.h>
45 #include <sys/kernel.h>
46 #include <sys/kauth.h>
47 
48 /*
49  * Reboot / shutdown the system.
50  */
51 void
52 kern_reboot(int howto, char *bootstr)
53 {
54 	static lwp_t *rebooter;
55 	lwp_t *l;
56 
57 	/*
58 	 * If already rebooting then just hang out.  Allow reentry for the
59 	 * benfit of ddb, even if questionable.  It would be better to call
60 	 * exit1(), but this is called from all sorts of places.
61 	 */
62 	l = atomic_cas_ptr(&rebooter, NULL, curlwp);
63 	while (l != NULL && l != curlwp) {
64 		(void)kpause("reboot", true, 0, NULL);
65 	}
66 	shutting_down = 1;
67 
68 	/*
69 	 * XXX We should re-factor out all of the common stuff
70 	 * that each and every cpu_reboot() does and put it here.
71 	 */
72 
73 	cpu_reboot(howto, bootstr);
74 }
75 
76 /* ARGSUSED */
77 int
78 sys_reboot(struct lwp *l, const struct sys_reboot_args *uap, register_t *retval)
79 {
80 	/* {
81 		syscallarg(int) opt;
82 		syscallarg(char *) bootstr;
83 	} */
84 	int error;
85 	char *bootstr, bs[128];
86 
87 	if ((error = kauth_authorize_system(l->l_cred, KAUTH_SYSTEM_REBOOT,
88 	    0, NULL, NULL, NULL)) != 0)
89 		return (error);
90 
91 	/*
92 	 * Only use the boot string if RB_STRING is set.
93 	 */
94 	if ((SCARG(uap, opt) & RB_STRING) &&
95 	    (error = copyinstr(SCARG(uap, bootstr), bs, sizeof(bs), 0)) == 0)
96 		bootstr = bs;
97 	else
98 		bootstr = NULL;
99 	/*
100 	 * Not all ports use the bootstr currently.
101 	 */
102 	kern_reboot(SCARG(uap, opt), bootstr);
103 	return (0);
104 }
105